The present invention relates in general to camcorders, and more particularly to a video correction apparatus for a camcorder in which representative points are selected for calculation of a correlation in detecting a motion vector which is necessary to correction of a video shake resulting from a tremble of the user's hands.
FIG. 1 is a view illustrating conventional motion vector detection regions and representative points in each of the motion vector detection regions. As shown in this drawing, an input video is divided into 4 equal motion vector detection regions for detection of a motion vector. Each of the divided 4 equal motion vector detection regions has 30 representative points which are set in fixed and uniform positions.
FIG. 2 is a block diagram of a conventional motion vector detector. As shown in this drawing, the conventional motion vector detector comprises a filter 1 for removing noise and high frequency components from a digital input video signal. An output signal from the filter 1 is applied to a representative point memory 2 and a correlation calculator 3.
The representative point memory 2 stores 30 pixel values which are set in fixed and uniform positions of each of the 4 motion vector detection regions. Namely stored as the representative points in the representative point memory 2 are 120 pixel values of the input video of one field. The 120 representative points from the representative point memory 2 are applied to the correlation calculator 3. The correlation calculator 3 calculates correlations of the 120 representative points from the representative point memory 2 to the surrounding pixel values. A maximum correlation detector 4 is adapted to detect a maximum one of the correlations calculated by the correlation calculator 3.
However, the conventional motion vector detector has a disadvantage in that it can not sufficiently utilize video data information which can make a picture comparison accurate, because it select the representative point data in the fixed positions. Also, the representative points required in obtaining the motion vector accurately are large in number. This results in complexity in the calculation and in a construction.